1. Field of the Invention
The present invention relates to a spring-barrel arrangement for a timepiece, including a fixed plate-like component which has a circular cutout in which a spring barrel is rotatably mounted by its corresponding circular outer contour, a barrel core which is rotatable coaxially in relation to the spring barrel, a helical tension spring having an inner end connected to the barrel core and an outer end connected to the spring barrel, a crown wheel having a toothed ring being fixed to the spring barrel, and a first wheel of a wheel train of the timepiece being fixed to the barrel core.
2. Description of the Related Art
In a known spring-barrel arrangement, an annular spring barrel is mounted in a cup-shaped depression of a plate-like component. A crown wheel, which is fixed to the annular spring barrel, projects into a large step of the depression. An annular part is connected to the plate-like component on an open side of the depression for axially fixing the crown wheel on an open side of the depression.
Since the spring barrel is only mounted in the small step of the depression, the bearing length in relation to the diameter of the spring barrel is small, with the result that the spring barrel in the depression can tilt and jam to a considerable extent in deviation from its desired axis.
Mounting the barrel core independently of the spring barrel also results in the barrel core deviating to a considerable extent from the desired axis, which, via the first wheel of the wheel train which is connected to the barrel core, adversely affects the accuracy of the movement or clockwork mechanism.